It has some large artwork, scrolling across L to R, fairly slowly in the main but there are parts where it's too quick and it's juddery. I know there's a seven second rule so should I just adhere to this and slow it all down and add pauses where necessary

OR

is there something else I can add? More MB (force MB is applied), a different fps... I'm not sure what else I can do here really.

Like M said: the link you sent is broken. without seeing your scroll I can tell you that motion blur could help - NOT FORCE MB -> this is for Effects not for Transformations. there is a certain speed and frame rate that at certain values will cause strobing, so you have to do a little trial and error to avoid the strobing. when we see the video we will know more.

Force MB is not for transformations, this is a common mistake. it is for effects (the native motion blur don't apply to effects) or for pre-rendered sequences (3D maybe) or precomps that due to render order issues, you would prefer to use Force MB instead of the Native motion blur. if you use this effect on a pre-comp you will get some motion blur but you could also get some artifacts and render time will be much slower - and without a good reason. this is from the Cycore Effects Manual:

what you need to do is to select motion blur for your layers inside your pre-comps by checking the switch for every layer, and don't forget to select the master switch in your timeline so you can preview the layers with the motion blur.

now you will get motion blur and your animation is less likely to strobe. having said that, the strobing could be a problem with the key-frames that control you camera i.e you made too much key-frames in the middle and messed with the interpolation.

Yeah I guess I'm gonna have to go through and MB all of it and check the switch. For some reason I remember it casuses issues with some of my layers but I'm not sure how or why right now (not currently with the project)

Thanks for the info on force motion blur though, I was a bit blinkered and actually didn't know that! Woops...

Is motion blur the main thing you would suggest? I feel like perhaps a lot of motion designers may work in a different frame rate and get better results?

I didn't want to rebuild the whole thing so this fix would be great, BUT I'm worried I'm still not doing it justice

frame rate is usually something you get (or ask) from the client and depends on their needs. 30/29.97fps will strobe less than 25fps or 23.97 but I believe that if you put the motion blur on - you will be fine. and if you have issues with it, you should solve them but when you get there tell us. also as I said, I would check the Null animation - if you put too many keyframes or messed with the interpolation, it could cause strobing.

Thanks for your help. I will let you know after the length render has finished. May try working in 30 fps to see the difference too. The null has very few animations on, movement is smooth (I would say?!?)

I wouldn't change the frame rate of compositions that I had keyframes on. because that will screw up the timeline and keyframes could find themselves between frames and not on frames. what I would do is put the whole thing in a precomp and only then change the frame rate. BUT I don't think that's your problem. do the motion blur and let's see

You can disguise judder with motion blur but unless you follow the rules for critical panning speed (rolling speed also) and move your artwork an even number of pixels per frame the move is going to be hard on the eyes. You have to adjust your design to work within the limitations of human retinal retention, frame rate and stroboscopic effects. It's that simple. Jack the motion blur way up and make it soft enough the judder is hidden or make the speed fit the formula or change the motion design. Character generators used for live broadcasts or on line production have speeds built in so you can pick show, medium or fast only. They mathematically eliminate the possibility of juddering edges by taking that control away from the user.

Thanks for the response Rick, those are interesting reads. I figured as much that the artwork would need to be changed to make it truly right and that motion blur etc would just be a rough fix to disguise.

Ideally I don't want to rebuild but I'm glad that it wasn't an error on my part to start with using the wrong FPS or similar issue..

Lorna - let's try something. I am assuming your animation is not intended for broadcast in PAL countries, so the 25fps is just a random choice of yours I gather. put your master comp inside another and change the frame rate of the new comp to 30Fps and render at that. then preview it again and see if the scrolling is better.

Be vary careful with non-standard frame rates. For now, to be safe when designing around motion problems, the maximum frame rate you should use for video that will be available to the general public should be 29.97 fps (NTSC standard) or 30 fps. YouTube and other streaming services will consistently and reliably deliver video up to 60i but the end user will only receive this higher frame rate if they have a fast enough connection to the internet and a system compatible with that frame rate. To be absolutely safe you should design your motion with a maximum frame rate of 29.97 or 30 fps. I use 29.97 because there are a lot of folks still watching video on televisions and mobile devices with this maximum frame rate. In a few years the majority of devices may be able to reliably handle 60P footage.

There have been arguments for years about the difference between film look and video look. There are lots of folks that think that they have to shoot at 24fps or 25, the standard frame rate in countries with 50HZ electrical service (PAL) but looking like film or a movie has a lot more to do with color grading than it does with frame rate. The problem with frame rates below 29.97 or 30 fps is that stroboscopic effects from motion get a lot worse as you slow down the frame rate. Standard film projectors have a butterfly shaped shutter between the lamp and the film that actually flashes the light on the film 48 times a second even though the film is running at 24 so your eyes and your brain get 49 flashes of light per second - two flashes per frame. This makes motion picture film easier to watch and eliminates flicker that can give a lot of people headaches and even introduce seizures in people with neuromuscular problems.

Unless my projects are specifically headed for theatrical projection all of them are at 29.97 or 59.94i (because cable tv is still sent to more than 90% of the world at 59.94 fps interlaced no matter what the original frame rate is but that's another subject) and I adjust the speed of the animation accordingly. You should consider anything other than 29.97 (30) fps in countries with 60hz electricity (NTSC) or 25 fps in countries with 60hz electrical power (PAL) non standard and stick to those frame rates for most of your work because the great majority of the playback devices that will see your work are set to those standard frame rates and there's nothing you can do to force them to use something else.

That's the end of my sermon. If you are working with things that move on a screen you have to follow the rules of motion to achieve the perception of smooth motion. There is no way around the physics of light or the physiology of the human brain.